Social Threat and Aging: Neural Mechanisms of Emotion Regulation Emotion regulation is critical for social behavior because social interactions can be the source of considerable stress. In particular, emotion regulation is essential for responding to social threat, which is defined as threats to self-esteem or social status. Such threats may be particularly salient in later life as individuals deal with loss of status and the negative stereotypes associated with old age. We will use behavioral methods in combination with functional MRI (fMRI) and diffusion tensor imaging (DTI) to investigate how older adults' emotion regulation system cope with social threat. Additionally, we will investigate factors that either challenge or facilitate the operation of this system. Taken together, the proposed 5 neuroimaging studies will achieve 3 specific aims. First, they will investigate how older adults' emotion regulation system responds to social threat. The emotion regulation system depends on the interplay between brain regions involved in generating emotions, such as the amygdala, and regions that exert control over emotional expression and experience, such as the prefrontal cortex. We will examine how the emotional regulation system operates in condition of threat to the individual at personal level (personal threat) and threat to the individual as a memory of a group (stereotype threat). Second, the proposed studies will also investigate how executive control resources modulate older adults' ability to regulate emotions elicited by social threat. Although healthy elderly are normally well adjusted at the emotional level, there is evidence that they maintain their emotional well-being by actively down-regulating negative emotions. This continuous emotion regulation strategy is taxing for executive control resources, which depend on frontoparietal networks that are known to decline with age. We will investigate how individual differences in executive resources modulate the operation of the emotional regulation system in older adults. Finally, the proposed studies will investigate how older adults' emotion regulation responses to social threat are enhanced by social support. Theoretical views suggest that close interpersonal relationships become increasingly important with age. Among other methods, we will study the role of social support by having a spouse or partner provide encouragement and physical contact under conditions of stereotype threat. Taken together, the studies proposed will clarify neural mechanisms of emotional regulation in older adults and how they respond to social threat. Given that emotion regulation depends on executive control networks that are known to be impaired by aging, this research has direct implications for understanding the interaction between cognitive and emotional processing in healthy aging, as well as in individuals at risk of Alzheimer's disease.